Pottery-kiln



(No Model.) 3 Sheets-Sheet 1.

1-. C. ROBERTS. POTTERY KILN.

No. 434,953. I Patented Aug. 26, 1890.

1212mm aw 3 Sheets-Sheet 2.

(No Model.) I

F. G. ROBERTS.

POTTERY KILN. No. 434,953. Patented Aug. 26, 1890.

Inventor 3 Sheets-Sheet 3.

(No M51161.

' F. G. ROBERTS.

POTTERY KILN.

Patented Aug. 26, 1890*.

W ll Inventoh UNITED STATES PATENT OFFICE;

FRANK O. ROBERTS, OF PHILADELPHIA, PENNSYLVANIA.

POTTERY-KILN.

SPECIFICATION forming part of Letters Patent N 0. 434,953, dated August26, 1890.

Application filed December 5, 1889.

.To all whom it may concern.-

Be it known that I, FRANK O. ROBERTS, of Philadelphia, and State ofPennsylvania,have invented certain new and useful Improvements inPottery-Kilns, whereof the following is a specification, reference beingbad to the accompanying drawings.

The object of my invention is to adapt the regenerative system toconvenientuse in a pottery-kiln, and the accompanying drawingsillustrate the invention in a convenient form for application to themost usual type of kiln.

In said drawings, Figure 1 represents a horizontal section through thekiln and chimney, showing in dotted lines the general arrangement of thefines. Fig. 2 is a central vertical section on the lines 20 w of Fig.'1,and Fig. 3 is a similarsection on the line mm of Fig. 1.

The kiln proper is constructed with a circular wall A, having adome-shaped roof B and a fioor C. At or near the center of said floor isa downtake-flue E above which is a raised disk-shaped cover D, having acentral opening V in its top and radial openings U around the sides soarranged as to cause a uniform outflow from all directions to the flueE. The flue E descends for a considerable distance and communicates witha horizontal flue E, which extends outward and rises into avalve-chamber G, containing a pivot-valve W. This may be the ordinaryform of reversing-valve used in regenerative furnaces, and it controlsthe communication with two horizontal flues II I, which extend aroundthe base of the kiln, preferably below the surface of the ground, asshown, and lead into a valve chamber K, in which is a second pivot-valveL, controlling communication with the chimney J and with that part ofthe chamber K which is open to the air. The flues H and I are preferablyformed with enlarged portions h t for a short distance on each side ofthe valve-chamber G, and this space may conveniently be filled withchecker-work such as is commonly used in regenerative furnaces. Thefines H and I are alternatively, of course, exitrfiues for the productsof combustion and entrance-fines for air, and the control of these finesby means of the pivot-valvesW and L is effected in the usual manner, theair being admitted at the chamber K.

Serial No. 332.847. (No model.)

The chamber G communicates with the intake-flue Q, which leads to anannular vertical intake-flue R, from whose upper end a number ofhorizontal intake-fines Svextend radially outward beneath the floor 0 ofthe kiln and communicate by short horizontal inletpassages on each sideof the vertical dischargejets T.

The main inlet-passage for gas is shown at M, (see dottted lines, Fig.1,) which communicates with an annular flue N, surrounding the base ofthe kiln and communicating at intervals by means of upwardly-inclinedintake-passages O with discharge jets P into the kiln proper. jets T forair are arranged in groups of three, each gas-jet being between twoair-jets, and each group may be situated in a short vertical piece ofbrick-work rising some distance above the floor of the kiln, so as toproject the mingled air and gas currents well up into the kiln beforecombustion takes'place.

The operation of the system is as follows: The gas (produced by means ofany suitable generator) is admitted to the passages MN 0 and flows intothe kiln through the jets P. The air is admitted at the valve-chamber Kand flows around through the flue I-I until it is deflected by thepivot-valve G into the passage Q; thence it rises through the annularflue R, and, flowing through the radial fines S, is discharged at thejets T on each side of the gas-jets P. The kiln is filled with thepottery arranged in the usual manner, and the firing is effected by thecombustion of air and gas, which is diffused throughout the kiln bymeans of the numerous outlets. The products of combustion pass outthrough the openings V U, descend by the downtakeflue E to thehorizontal continuation thereof F, and rise into the valve-chamber G,where they are deflected by the valve WV into the flue I, by which theypass to the valve-chamber K, where they are deflected by the valve Linto the chimney J, and 'escape. The courses of entering air and gas areindicated by the arrows to, and the course of the outgoing products ofcombustion is indicated by the arrows b, the direction of which ofcourse will be reversed with each reversal of the valves W and L, Ifpreferred, the gas to be burned may also be heated by means of a Thejets P for gas and the similar regenerative systemsuch as, for instance,a vertical or horizontal subdivision of the annular flues II and Ioneportion of which can thus be used to heat the air and the other portionto heat the gas, while both subdivisions of the flues can be heated bythe outgoing productions of combustion.

I am of course aware that the application of the regenerative system toa pottery-kiln is not, broadly speaking, new, and I do not claim suchapplication broadly. I have found,

however, that to make the principle available for use in a pottery-kilnit is essential that the flow of the currents within the kiln propershould always be in the same direction. If, as is the case with ordinaryregenerative systems, the openings into the kiln are alternately used asexit-fines for products of combustion and entrance-fines for air, it isnot practicable to maintain a heat sufficiently uniform to properly burnpottery, and an irregular and defective product will result. My presentinvention overcomes this diffic'ulty, and one of its most importantfeatures lies in the fact that the reversal of direction of the currentstakes place outside of the kiln only, this mode of operation beingpermitted by the use, in connection with the permanent inlet and outletpassages,of a pair of exterior regeneratorpassages. So faras I am awarethis principle has never been developed in any previous application ofthe regenerative system to pottery manufacture, and I therefore desireto claim its embodiment broadly and irrespective of the particulararrangement of the inlet and outlet passages, it being only necessarythat they should be in such a symmetrical relation to the kiln as shallproduce a thorough and uniform distribution of the heat.

Having thus described my invention I claim 1. I11 a regenerativepottery-kiln, the combination, with the kiln proper, of a centraldowntake-passage and flue leading therefrom, a pair ofregenerator-passages communicating with said flue, a series ofintake-passages having jets arranged circumferentially within said kilnand leading into the same, a flue connecting said intake-passages withthe regenerator-passages, a chimney, an air-inlet, a pair ofreversing-valves controlling the communication between theregenerator-passages and the said fines, air-inlet, and chimney, and agas-inlet having suitable passages leading into said kiln, substantiallyas set forth.

2. In a regenerative pottery-kiln, the combination of a kiln proper, acentral downtakepassage having a cover and radial and vertical openingsin said cover, a flue leading from said downtake, a pair of semicircularregenerator-passages communicating with said flue, an.air-inlet andchimney, an intake-flue communicating with said regenerator-passages,reversing-valves controlling the communication between theregeneratorpassages and the said chimney, said air-inlet, and saidintake-flue, an annular passage leading from the intake-flue andsurrounding the downtake-fiue, radial passages leading from said annularpassage, inlet-jets arranged in pairs around the interior of said kilnand connected with said radial passages, a main inlet for gas, anannular passage connected therewith, and upwardly-inclined intake-passages leading from said annular passage to the interior of the kilnand arranged between the pairs of air-inlet jets, substantially as setforth.

3'. In a regenerativepottery-kiln, the combination, with the kilnproper, of a permanent outlet-passage for products of combustion, a pairof regenerator-passages communicating therewith, a plurality ofpermanent inlet-passages for gas and air having dischargeorificesdistributed in substantial symmetry within said kiln, flues connectingthe air-inlet passages with the regenerator-passages, a chimney, a maingas-inlet, and a pair of reversing-valves controlling the communicationbetween said regenerator-passages, said outlet-passages, saidair-passages, said chimney, and said main air-inlet, substantially asset forth.

FRANK O. ROBERTS. \Vitnesses:

THEo. TOPLIN, JAMES H. BELL.

